Method and apparatus for enabling synchronization

Abstract

Apparatuses and methods for enabling synchronization are provided. The solution comprises receiving ( 300 ), from a network entity, a random-access indication message indicating whether a transmission of at least one physical random access channel, PRACH, uses at least one random access resource corresponding to or associated with one or more network entities, and transmitting ( 302 ) the at least one of the PRACH based on the random-access indication message.

1 .- 24 . (canceled) 
     
     
         25 . A method for a terminal device, comprising:
 receiving, from a network entity, a random-access indication message indicating whether a transmission of at least one physical random-access channel (PRACH) uses a plurality of random-access resources corresponding to or associated with one or more network entities, wherein the plurality of random-access resources comprise the following: random-access preamble index, synchronisation signal/physical broadcast channel, SS/PBCH, index, and random-access channel occasion, wherein the random-access indication message is received in downlink control information (DCI) and via medium access control (MAC) control element, wherein the DCI indicates whether the terminal device is to perform a contention-free random-access (CFRA) procedure or a contention-based random-access (CBRA) procedure, wherein the random-access indicating message comprises an indication of random-access resources to be used for contention-based random-access corresponding to or associated with at least one of the one or more network entities, wherein the random-access indicating message comprises at least a second random-access resource for contention-free random-access corresponding to or associated with at least one of the one or more network entities; and   transmitting the at least one of the PRACH based on the random-access indication message, wherein the transmitted at least one PRACH is using the plurality of random-access resources corresponding to or associated with a network entity for which a corresponding timer has expired.   
     
     
         26 . The method of  claim 25 , wherein the receiving from the network entity comprises receiving from a transmission-reception point. 
     
     
         27 . The method of  claim 25 , wherein the receiving from the network entity comprises receiving from a physical cell. 
     
     
         28 . The method of  claim 25 , wherein the receiving from the network entity comprises receiving over a control resource set group. 
     
     
         29 . The method of  claim 28 , further comprising:
 determining a presence of at least one second random-access resource in the message based on an indication carried in the message or based on an indication carried separately.   
     
     
         30 . The method of  claim 29 , wherein the DCI provides an indication to transmit two PRACHs. 
     
     
         31 . The method of  claim 30 , further comprising:
 determining that the DCI includes, in addition to a first random-access preamble index a first synchronisation signal/physical broadcast channel (SS/PBCH) index, and a first random-access channel occasions further random-access preamble indexes, further SS/PBCH indexes, and further random-access channel occasions for the transmission.   
     
     
         32 . The method of  claim 31 , further comprising determining a presence of other preamble indexes, synchronisation signal block (SSB) indexes, and random-access occasions in DCI. 
     
     
         33 . An apparatus comprising:
 a processor; and   a memory comprising computer-executable instructions that, when executed by the processor, cause the apparatus to perform the following operations:   receiving, from a network entity, a random-access indication message indicating whether a transmission of at least one physical random-access channel (PRACH) uses a plurality of random-access resources corresponding to or associated with one or more network entities, wherein the plurality of random-access resources comprise the following: random-access preamble index, synchronisation signal/physical broadcast channel, SS/PBCH, index, and random-access channel occasion, wherein the random-access indication message is received in downlink control information (DCI) and via medium access control (MAC) control element, wherein the DCI indicates whether the terminal device is to perform a contention-free random-access (CFRA) procedure or a contention-based random-access (CBRA) procedure, wherein the random-access indicating message comprises an indication of random-access resources to be used for contention-based random-access corresponding to or associated with at least one of the one or more network entities, wherein the random-access indicating message comprises at least a second random-access resource for contention-free random-access corresponding to or associated with at least one of the one or more network entities; and   transmitting the at least one of the PRACH based on the random-access indication message, wherein the transmitted at least one PRACH is using the plurality of random-access resources corresponding to or associated with a network entity for which a corresponding timer has expired.   
     
     
         34 . The apparatus of  claim 33 , wherein the receiving from the network entity comprises receiving from a transmission-reception point. 
     
     
         35 . The apparatus of  claim 33 , wherein the receiving from the network entity comprises receiving from a physical cell. 
     
     
         36 . The apparatus of  claim 33 , wherein the receiving from the network entity comprises receiving over a control resource set group. 
     
     
         37 . The apparatus of  claim 36 , wherein the computer-executable instructions, when executed by the processor, cause the apparatus to perform the following operations:
 determining a presence of at least one second random-access resource in the message based on an indication carried in the message or based on an indication carried separately.   
     
     
         38 . The apparatus of  claim 29 , wherein the DCI provides an indication to transmit two PRACHs. 
     
     
         39 . The apparatus of  claim 38 , wherein the computer-executable instructions, when executed by the processor, cause the apparatus to perform the following operations:
 determining that the DCI includes, in addition to a first random-access preamble index a first synchronisation signal/physical broadcast channel (SS/PBCH) index, and a first random-access channel occasions further random-access preamble indexes, further SS/PBCH indexes, and further random-access channel occasions for the transmission.   
     
     
         40 . The apparatus of  claim 39 , wherein the computer-executable instructions, when executed by the processor, cause the apparatus to perform the following operations:
 determining a presence of other preamble indexes, synchronisation signal block (SSB) indexes, and random-access occasions in DCI.   
     
     
         41 . A system comprising:
 an apparatus;   a processor; and   a memory comprising computer-executable instructions that, when executed by the processor, cause the apparatus to perform the following operations:   receiving, from a network entity, a random-access indication message indicating whether a transmission of at least one physical random-access channel (PRACH) uses a plurality of random-access resources corresponding to or associated with one or more network entities, wherein the plurality of random-access resources comprise the following: random-access preamble index, synchronisation signal/physical broadcast channel, SS/PBCH, index, and random-access channel occasion, wherein the random-access indication message is received in downlink control information (DCI) and via medium access control (MAC) control element, wherein the DCI indicates whether the terminal device is to perform a contention-free random-access (CFRA) procedure or a contention-based random-access (CBRA) procedure, wherein the random-access indicating message comprises an indication of random-access resources to be used for contention-based random-access corresponding to or associated with at least one of the one or more network entities, wherein the random-access indicating message comprises at least a second random-access resource for contention-free random-access corresponding to or associated with at least one of the one or more network entities; and   transmitting the at least one of the PRACH based on the random-access indication message, wherein the transmitted at least one PRACH is using the plurality of random-access resources corresponding to or associated with a network entity for which a corresponding timer has expired.   
     
     
         42 . The system of  claim 41 , wherein the receiving from the network entity comprises receiving from a transmission-reception point. 
     
     
         43 . The system of  claim 42 , wherein the computer-executable instructions, when executed by the processor, cause the apparatus to perform the following operations:
 determining a presence of at least one second random-access resource in the message based on an indication carried in the message or based on an indication carried separately; and   wherein the DCI provides an indication to transmit two PRACHs.   
     
     
         44 . The system of  claim 43 , wherein the computer-executable instructions, when executed by the processor, cause the apparatus to perform the following operations:
 determining that the DCI includes, in addition to a first random-access preamble index a first synchronisation signal/physical broadcast channel (SS/PBCH) index, and a first random-access channel occasions further random-access preamble indexes, further SS/PBCH indexes, and further random-access channel occasions for the transmission.